Mine lining and conveyor combination

ABSTRACT

The roof of an underground excavation is supported by a lining, and a conveyor extending along the mine face is reinforced at least in a section facing away from the mine face and supporting at least one cantilever beam and a hydraulic advancement assembly. A floor base of the lining is provided with recesses for guidingly accommodating the cantilever beam in the floor base, so as to permit relative movement of the conveyor and the lining in the direction perpendicular to the mine face, the lining and the conveyor alternately serving as retaining means for each other during the step-wise advancement of the combination.

United States Patent 1191 Spies et al.

14 1 July 29, 1975 1 1 MINE LINING AND CONVEYOR COMBINATION [73] Assignee: Bochumer Eisenhutte I-Ieintzmann &

Co., Bochum, Germany [22] Filed: May 18, 1973 [21] Appl. No; 361,623

3,431,738 3/1969 Groetschel 61/45 D 3,482,878 12/1969 Floter 299/32 3,504,944 4/1970 11012 et a1. 299/32 3,570,255 3/1971 Shuttleworth 299/33 X 3,640,581 2/1972 Rassmann et a1. 299/32 FOREIGN PATENTS OR APPLICATIONS 1,937,308 2/1971 Germany 6l/45 D 262,050 l/l97l U.S.S.R....... 61/45 D Primary Examiner-Dennis L. Taylor Attorney, Agent, or FirmMichael S. Striker [57] ABSTRACT The roof of an underground excavation is supported by a lining, and a conveyor extending along the mine face is reinforced at least in a section facing away from the mine face and supporting at least one cantilever beam and a hydraulic advancement assembly. A floor base of the lining is provided with recesses for guidingly accommodating the cantilever beam in the floor base, so as to permit relative movement of the conveyor and the lining in the direction perpendicular to the mine face, the lining and the conveyor alternately serving as retaining means for each other during the step-wise advancement of the combination.

8 Claims, 4 Drawing Figures MINE LINING AND CONVEYOR COMBINATION BACKGROUND OF THE INVENTION The present invention relates to a lining for underground excavations, in particular such which is to be used in combination with a conveyor for stepwise advancement toward the mine face.

Linings for underground excavations serving the purpose of supporting the mine roof and, consequently, protecting the personnel and valuable mining equipment from cave-in are already known. They generally comprise a floor base. and a shield which is pivotably attached to the same so as to rotate in relation thereto and having an arcuate, possibly multi-part, configuration. The shield extends over the floor base in direction toward the mine face, and supports on its free end a roof cap projecting beyond the shield toward the mine face. A pit prop engages the floor base and the shield for pushing the roof cap toward the mine roof. Furthermore, there are also known arrangements, which will be discussed later, for attaching such linings to a conveyor so as to accomplish a greater degree of stability of the lining and render possible alternate movement of either the conveyor or the lining toward the mine face in the course of mining operations.

The conventional linings of this kind have the disadvantage that in view of the requirement for sufficient stability of the lining it is impossible to forward the shield and the roof cap to such an extent that the conveyor is fully covered, which is a necessary condition for proper protection of the personnel and conveyor against cave-in of the mine roof, particularly if the same consists of a breakable or unstable material. However, experience has shown the desirability of utilization of such linings for exactly such conditions, particularly in connection with coal cutting, wherein the base elements of the lining are spaced away from the conveyor by a complete advancement step, to be advanced toward the conveyor at the time of passage of the mining machine and prior to advancement of the conveyor, so that the mine roof is supported by the roof cap in the region above and beyond the conveyor immediately after the passage of the mining machine, so that the time period elapsing between the exposure of the unsupported roof and the application of the roof cap thereto amounts to only a few seconds.

In spite of the other advantages inherent thereto, the above described arrangement is disadvantageous in that the base elements cannot be advanced close enough toward the mine face to satisfy the requirement of sufficient stability of the lining, in view of the presence of the conveyor between the base elements and the mine face.

In order to render possible the advancement of the lining as discussed above. it is already known from another lining and conveyor combination to elevate the conveyor by means of a rigid understructure, so that the floor base itself or skid-shaped projections thereof can extend underneath the understructure of the conveyor during the advancement of the lining toward the mine face. so as to assure its stability.

However, this conveyor understructure brings about with it other disadvantages. Besides contributing to increase in the material and cost expenditure, the provision of the understructure considerably increases the loading height of the conveyor. so that especially the SUMMARY OF THE lNVENTlON It is a general object of the invention to overcome the disadvantages of the prior art.

A more particular object of the present invention is to avoid the drawbacks of the conventional combinations of advancing mine linings and conveyors.

It is a further object of the invention to provide a mine lining which has a high degree of stability.

A concomitant object of the present invention is to provide a combination of a lining and a conveyor in which the conveyor is sufficiently low so as to permit efficient coal removal and the lining extends above and beyond the same so as to protect the mining equipment from a cave-in.

In pursuance of these objects and others which will become apparent hereinafter, one feature of the invention resides in reinforcing one side of the conveyor and attaching thereto at least one rigid cantilever beam projecting toward the floor base of the lining. The floor base is provided with recess means for guidingly accommodating the cantilever beam so that the displacement of the cantilever beam in relation to the floor base is limited to one direction only, namely the direction of the axis of the cantilever beam which is perpendicular to the mine face, during the advancement of either the lining or the conveyor.

According to the above described embodiment of the invention, it is possible to achieve in a relatively simple manner and with relatively simple means an increased stability of the lining, which has been heretofore achieved only by the utilization of a complicated and expensive conveyor understructure or frame with its inherent disadvantages, mainly the difficult and unreliable loading of the fine coal. The requirements for increased coal-handling capability which have been made of conveyors in recent years, have resulted in the development of robust and massive conveyors which require only relatively minor changes to adapt them for use as a retaining element serving to increase the stability of the lining. This, in turn. makes it possible to omit the previously required extensions or projections of the floor base of the lining without impairing the stability and the function of the lining.

In a currently preferred embodiment of the present invention, the cantilever beams which are positively guided in the recess means of the floor base of the lining are rigidly but dismountably attached to a side of the conveyor which faces away from the mine face and which is reinforced in any conventional manner at least in the section of the conveyor where the cantilever beams are attached. One of the possible methods of reinforcement is attaching a reinforcing steel sheet to the affected conveyor side so as to extend along the mine floor, an expedient which in no way impairs the complete removal of the mined coal. It is evident that since the cantilever beam is accommodated in the floor base so as to have'only one degree of freedom of movement in relation thereto, all forces and moment trying to tilt the lining either when in its fixed position or during the advancement thereof, are counterbalanced by the forces in the cantilever beam which are, in turn, transmitted to the conveyor. Since the side of the conveyor which faces toward the mine face is in any case and under all circumstances closer to the mine face than the free end of the shield which carries the pivot supporting the roof cap, the possibility of tilting of the lining is eliminated. In order to increase the stability and rigidity of the conveyor, the reinforcing steel sheets may be constructed as steel plates which are welded to the side of the conveyor so as to extend underneath the same and to enclose the lower run of the conveyor at least in the region of the respective cantilever beams.

The transmission of the tilting forces and moments from the floor base to the cantilever beams can be accomplished either by accommodating the cantilever beams in corresponding recesses provided in the floor base itself, or by providing additional guiding means which are located and supported between the beams of the floor base.

In a preferred embodiment of the invention corresponding to the first possibility outlined above, the floor base comprises two beams each of which is provided with a channel extending in the longitudinal direction of the respective beam and having crosssectional dimensions corresponding to those of the corresponding cantilever beam, and the cantilever beam is accommodated in each of these channels so as to be movable in the longitudinal direction thereof only. The two beams are interconnected by transverse beam means, and a cylinder and piston assembly is attached at one of its ends to one of these transverse beam means and intermediate the two beams, the other end being attached to the conveyor so as to induce an advancing movement of either the lining or the conveyor when the cylinder and piston assembly is actuated, depending on the direction of movement of the assembly.

However, there are other occasions in which it may prove to be advantageous to provide a lining and conveyor assembly constructed in accordance with the other possibility outlined above. In this case, according to the invention, the cantilever beam is constructed as a box section which is attached to the side of the conveyor and which is adapted for accommodation of the cylinder and piston assembly, and the floor base of the lining comprises two beams, two pairs of transverse beams interconnecting the two beams and defining elongated recess means for accommodating the cantilever beam therein, and guidance means for limiting the movement of the cantilever beam to one direction only, namely the direction of its longitudinal axis.

Regardless of which possibility is chosen, however, it is advantageous to construct the cantilever beams, which are guided in the recess means of the floor base, in such a manner that the length of the cantilever beams exceeds the length of the floor base, and thus the recess means, by at least the length of the stroke of the cylinder and piston assembly during the advancement of either the conveyor or the lining toward the mine face.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation. together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side-elevational view of a lining and conveyor assembly according to one embodiment of the invention, installed in an underground excavation;

FIG. 2 is a top plan view ofa floor base with a cantilever beam of the embodiment in FIG, 1, as seen in the direction of the arrow X of that FIGURE;

FIG. 3 is a cross-sectional view taken on the line AB of FIG. 2; and

FIG. 4 is a further embodiment of the floor base and the cantilever beam, in a view corresponding to FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows in cross-section an underground excavation having a mine face 1, a mine filling or cavity 2, a mine floor 3 and a mine roof 4.

A conveyor 5 which can be constructed, for instance, as a double chain scraper conveyor, extends along the mine face, and a mining machine 6 is guided on the conveyor 5 for displacement in relation thereto in the longitudinal direction of the same and comprises a driven cutter 7 for undercutting the mine face.

The lining according to the invention comprises a floor base 8 having two sides, one of which serves for supporting a shield 9 and the other one of which extends towards the mine face I. The shield 9 is attached to the one side of the floor base so as to be rotatable in relation thereto, extends over the same towardsthe mine face I, and comprises means for supporting a roof cap 10. In the illustrated embodiment, the supporting means comprise a pivot 11 supported in a free end of the shield 9 above the conveyor 5, and the roof cap 10 isffree to pivot about the same. 7 An extendable hydraulic cylinder 12 is arranged between, and engages, the floor base 8 and the shield 9 so as to push the shield 9 and thus the roof cap 10 into engagement with the mine roof 4. It is to be understood that the invention is not limited to only one pit prop 12; rather there may be provided two or more such pit props. In a preferred embodiment, the shield 9 includes a plurality of mutually spaced trough-shaped bars whose flanges extend outwardly in relation to the shield 9.

Referring now particularly to FIG. 2. it is to be seen therein that the frame-shaped floor base 8 comprises two elongated beams 13 each having two ends, the ends facing away from the mine face 1 comprising brackets 14 serving for accommodation therein of the pivot 15 connecting the shield 9 to the floor base 8 for pivotal displacement in relation thereto.

The elongated beams 13 are interconnected at their ends facing away from the mine face I by a first pair of transverse beams 16 and on the other end by a second pair of transverse beams 17, one of the transverse beams 17 being provided with means I8 for accommodation of, and engagement with, the pit prop 12. While the means 18 are illustrated as a recess for accommodating an end of the pit prop 12, it is evident that any other suitable means can be substituted therefor.

It can be further seen from FIG. I when considered in connection with FIG. 2 that a cantilever beam 19 is rigidly connected to a side 50 of the conveyor 5 facing away from the mine face. The cantilever beam is longer than the floor base 8 by approximately twice the contemplated advancement step of the lining and conveyor. The lower run of the conveyor 5 is closed by a plate 5b which is welded to the side 5a of the conveyor at least in the region of attachment of the cantilever beam 19, so that the conveyor 5 is particularly rigid in this region, and, consequently, in cooperation with an attachment plate 19a of the cantilever beam 19, it can serve as a rigid extension of the cantilever beam 19 toward the mine face 1.

FIG. 3 shows that the cantilever beam 19 is constructed as a hollow, closed box section which is guided in the corresponding guiding recesses of the transverse beams 16 and 17 associated with the two elongated beams 13 of the floor base 8 so as to be displaced only in the longitudinal direction thereof, and whose inner hollow space serves for an exchangeable accommodation of a cylinder and piston assembly which can be hydraulically actuated to move in either one of the longitudinal directions of the same. The assembly 20 is attached to the side 50, the cantilever beam 19 or the attachment plate 19a at one end, and to the transverse beam 16 or the elongated beams 13 at the other end in any well known manner, for instance as shown in the drawings. For example, the box section of the cantilever beam can be provided with a slot in its end portion and a pin may be accommodated in the same and engage the transverse beams 16 and an end of the cylinder and piston assembly 20. In this manner it is achieved that when pressurized hydraulic medium is delivered to one side of the cylinder and piston assembly 20 and the lining braces against the mine roof and floor, the conveyor 5 and the associated cantilever beam 19 are advanced toward the mine face. On the other hand, when the other side of the assembly 20 is actuated by the pressurized medium and the hold of the lining with the mine roof and floor is released, the lining is displaced on the cantilever 19 toward the conveyor 5, using the same as retaining means.

FIG. 4 shows a different embodiment of the floor base 8 according to the invention, wherein the transverse beams 17 with the pit prop engaging means 18 have been omitted for the sake of clarity. This embodiment utilizes two cantilever beams 19 which are accommodated and positively guided in the corresponding channels or recesses in the two elongated beams 13 of the floor base 8, and the cylinder and piston assembly 20 is situated intermediate the two elongated beams I3. The one end of the assembly 20 is rigidly attached to a transverse beam 21, for instance by welding, and an end portion of a piston rod 22 of the assembly 20 is rigidly connected to the conveyor 5. In all other respects, the embodiment of FIG. 4 corresponds to that of FIGS. 1-3.

It will be understood that each of the elements described above. or two or more together, may also find a useful application in other types of constructions, differing from the types described above.

While the invention has been illustrated and described as embodied in a mine lining and conveyor combination. it is not intended to be limited to the details shown. since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge. readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and described to be protected by Letters Patent is set forth in the appended claims:

1. In an excavating arrangement, a combination comprising a roof support having a floor-engaging base, a shield pivoted to said base and extending over the same toward the excavation face, a roof-engaging cap pivoted to said shield and extending beyond the same toward the excavation face, and a pit prop extending between said base and said shield; conveyor means extending along the excavation face underneath said cap and also engaging the excavation floor; means for displacing said roof support and said conveyor means relative to one another and sequentially toward the excavation face; and means connecting said roof support with said conveyor means and limiting said displacement of said roof support and of said conveyor means relatively to each other to linear displacement only in direction towards the excavation face while preventing any other relative displacement of said roof support and conveyor means, so that said conveyor means acts as an extension of said floor-engaging base of said roof support and reduces the tendency of the latter to tilt toward the excavation face about said floor-engaging base.

2. A combination according to claim I, and further comprising means for removing the material from the region of said conveyor means, said removing means being supported on the latter.

3. A combination according to claim 1, wherein said connecting means includes at least one beam rigidly connected to said conveyor means and extending therefrom toward said roof support.

4. A combination according to claim 3, wherein said displacing means includes a cylinder-and-piston assembly extending between and engaging said conveyor means and roof support.

5. A combination according to claim 4, comprising an additional beam spaced from the first-mentioned beam, said base comprising two base beams with provided with a channel for positive guidance of one of said beams, and transverse beam means for interconnecting said two base beams, and wherein said cylinder and piston assembly is rigidly connected to said transverse beam means intermediate said two base beams.

6. A lining according to claim 4, wherein said beam is longer than said floor base by at least the length of a stroke of said cylinder and piston assembly.

7. A combination according claim 4, wherein said beam comprises a box section adapted for accommodation of said cylinder-and-piston assembly; and wherein said base comprises two base beams parallel to said beam, and two pairs of transverse beams normal to said base beams and interconnecting the same, said connecting means including female guiding means mounted on said transverse beams for positively guiding said beam therein.

8. A combination according to claim 3, and comprising means for reinforcing said conveyor means at least along a section thereof and wherein said beam is rigidly but detachably connected to said conveyor means in said reinforced section of the same.

I i 1.! III 

1. In an excavating arrangement, a combination comprising a roof support having a floor-engaging base, a shield pivoted to said base and extending over the same toward the excavation face, a roof-engaging cap pivoted to said shield and extending beyond the same toward the excavation face, and a pit prop extending between said base and said shield; conveyor means extending along the excavation face underneath said cap and also engaging the excavation floor; means for displacing said roof support and said conveyor means relative to one another and sequentially toward the excavation face; and means connecting said roof support with said conveyor means and limiting said displacement of said roof support and of said conveyor means relatively to each other to linear displacement only in direction towards the excavation face while preventing any other relative displacement of said roof support and conveyor means, so that said conveyor means acts as an extension of said floor-engaging base of said roof support and reduces the tendency of the latter to tilt toward the excavation face about said floor-engaging base.
 2. A combination according to claim 1, and further comprising means for removing the material from the region of said conveyor means, said removing means being supported on the latter.
 3. A combination according to claim 1, wherein said connecting means includes at least one beam rigidly coNnected to said conveyor means and extending therefrom toward said roof support.
 4. A combination according to claim 3, wherein said displacing means includes a cylinder-and-piston assembly extending between and engaging said conveyor means and roof support.
 5. A combination according to claim 4, comprising an additional beam spaced from the first-mentioned beam, said base comprising two base beams with provided with a channel for positive guidance of one of said beams, and transverse beam means for interconnecting said two base beams, and wherein said cylinder and piston assembly is rigidly connected to said transverse beam means intermediate said two base beams.
 6. A lining according to claim 4, wherein said beam is longer than said floor base by at least the length of a stroke of said cylinder and piston assembly.
 7. A combination according claim 4, wherein said beam comprises a box section adapted for accommodation of said cylinder-and-piston assembly; and wherein said base comprises two base beams parallel to said beam, and two pairs of transverse beams normal to said base beams and interconnecting the same, said connecting means including female guiding means mounted on said transverse beams for positively guiding said beam therein.
 8. A combination according to claim 3, and comprising means for reinforcing said conveyor means at least along a section thereof and wherein said beam is rigidly but detachably connected to said conveyor means in said reinforced section of the same. 